Then we all die because the sun would blow up the earth.
Answer: an electromagnetic wave of a frequency between about 104 and 1011 or 1012 Hz, as used for long-distance communication.
Explanation:
<span>Biotic and Abiotic Factors Form Ecosystems. In a healthy forest community, interacting populations might include birds eating insects, squirrels
eating nuts from trees, mushrooms growing from decaying leaves or bark,
and raccoons fishing in a stream. In addition to how individuals in a
population interact with each other, let me know if it helps :)</span>
The fraction of the original amount remaining is closest to 1/128
<h3>Determination of the number of half-lives</h3>
- Half-life (t½) = 4 days
- Time (t) = 4 weeks = 4 × 7 = 28 days
- Number of half-lives (n) =?
n = t / t½
n = 28 / 4
n = 7
<h3>How to determine the amount remaining </h3>
- Original amount (N₀) = 100 g
- Number of half-lives (n) = 7
- Amount remaining (N)=?
N = N₀ / 2ⁿ
N = 100 / 2⁷
N = 0.78125 g
<h3>How to determine the fraction remaining </h3>
- Original amount (N₀) = 100 g
- Amount remaining (N)= 0.78125 g
Fraction remaining = N / N₀
Fraction remaining = 0.78125 / 100
Fraction remaining = 1/128
Learn more about half life:
brainly.com/question/26374513
Answer:
Base Mg(OH)2 does neutralise the acid and is 12g in excess.
Explanation:
2HCL +Mg(OH)2 -> MgCl2 + 2H20
2 * 36.458 g of HCL react with 58.319 g of Mg(OH)2 to neutralise it.
72.916 HCl reacts with 58.319 g of the base.
So 20 g HCl reacts with (58.319/72.916) * 20 = 16g.
There are 28 g of Mg(OH)2 so the base does neutralise all the acid.
The Mg(OH)2 is 28 - 16 = 12 g in excess.
